1. Field of the Invention
The present invention relates to a fuel supply device of an engine.
2. Description of the Related Art
In a known so-called "air blast" valve, the opening and closing operation of the nozzle opening is electromagnetically controlled by a needle to inject fuel by pressurized air. A pressurized air passage extending from the nozzle opening along the needle is formed around the needle and connected to a pressurized fuel source. A nozzle chamber which is open to the pressurized air passage is provided, and the nozzle of the fuel injector is arranged at the deep interior of the nozzle chamber. After fuel is injected from the fuel injector toward the needle, the needle opens the nozzle opening, whereby the fuel thus injected is injected from the nozzle opening of the air blast valve together with pressurized air (see International Publication No. W087/00583). In this air blast valve, it is possible to obtain a good atomization of fuel by pressurized air of low pressure.
However, where the nozzle of the fuel injector is arranged at the deep interior of a nozzle chamber which is open to the pressurized air passage, as in the above-mentioned air blast valve, when the needle opens the nozzle opening, the pressurized air does not substantially flow within the nozzle chamber. As a result, since the fuel stuck to the inner wall of the nozzle chamber cannot be carried away by the pressurized air, a problem occurs in that the injected fuel will accumulate within the nozzle chamber.